The present invention relates generally to the field of writing instruments and in particular to a new and useful pen clip having a bias spring held on the clip arm to provide a gripping force while reducing the likelihood of breaking due to wear.
Clips secured to the cap or barrel of a writing instrument for holding the writing instrument in a shirt pocket or on a pad of paper are generally known. Many prior clips are biased simply by a bent strip of metal, which form a U-shape, similar to a leaf spring. One end of the strip of metal is secured to a writing instrument barrel or cap. over time, flexion of the strip can lead to permanent deformation or the connecting strip breaking and the clip becoming irreparably detached from the writing instrument.
A pen clip of this type is illustrated by U.S. Pat. No. 1,923,153, in which the clip arm is made of a metal and has a small ball at the end to assist a person in putting the clip over the edge of a pocket. The clip relies upon the deformation of the clip arm so that the clip can be fit over a pocket edge.
U.S. Pat. No. 1,926,852 discloses a pen clip having a spring formed by a planar strip of metal connecting the clip arm to a pen cap. The spring is simply a resilient piece of metal secured to the pen cap at one end and having the clip arm mounted over the other end. The clip arm movement is limited by the upper end of the clip arm resting against the side of the cap and the surface of the spring.
Some prior pen clips include metal coils which are non-functional as springs and are used only to secure a clip to a writing instrument or other object.
U.S. Pat. No. 854,378, for example, has a pen clip formed from a single length of wire which is bent into a loop in the center to form a clip arm. The ends of the loop are wound together into a coil having the coil longitudinal axis parallel to the length of the clip arm. The coil is adapted to fit over varying diameter writing instruments, while the loop extends from one end of the coil to form a clip on the side of a writing instrument. The loop simply deforms away from the side of the pen or pencil that the coil has been fitted over. The coil is expected to tightly hold the clip to the pen and is not intended to deform or compress when the clip arm is pivoted away from the writing instrument.
U.S. Pat. No. 1,211,463 teaches a device holder having a coil holding a tube and gripping jaws formed by the ends of the coil which can be supported on a shirt pocket. The coil is not intended to compress or deform axially as the tube prevents that type of movement. The gripping jaws are biased closed by the coil and can hold objects.
Other clips have rigid clip arms with a perpendicular upper section connected to a writing instrument. The upper sections are used to pivotally w hold the clip to the writing instrument, such as in U.S. Pat. No. 2,468,699, which shows a pen clip mounted to a pen cap by a spring-biased fulcrum at the top of the pen cap. The clip arm may be pivoted away from the side of the pen cap, causing the upper end of the clip arm to move against a spring mounted perpendicular to the clip inside the writing instrument body.
A pen clip having the enclosed end inside the cap biased against a coil spring positioned vertically inside the cap is taught by U.S. Pat. No. 2,498,857. The clip arm extends out of the cap through a slot which permits the clip to pivot away from the side of the pen cap. The horizontal enclosed end of the cap is held between the upper end of the cap and the spring. The spring and clip enclosed end are mounted around a cylindrical threaded connector which also closes the end of the cap.
These types of clips suffer from the problem of complex manufacturing requirements to incorporate the spring mechanism inside the writing instrument. Further, the clip is not rigidly held to the writing instrument, but instead, has a flexible connection which is subject to breaking or wear which is not easily repairable. Since the upper end of the clip arm has to pass through the writing instrument body, the side of the writing instrument can be damaged, and the clip arm is still subject to breaking from excessive force applied to the bent portion.
It is an object of the present invention to provide a clip for a writing instrument which has a robust biasing mechanism external of the writing instrument body.
It is a further object of the invention to provide a clip using a coil spring to bias the clip arm.
Yet another object of the invention is to provide a clip biasing mechanism with a significantly reduced likelihood of breaking or permanently deforming.
A further object of the invention is to provide a clip for a writing instrument which is biased toward the writing instrument body and connected to the writing instrument body by two separate components.
Accordingly, a clip for a writing instrument has a clip arm with two ends, the upper end being threaded to receive a fastener, a spring fit over the upper end of the clip arm, and a flange adjacent the upper end having a diameter larger than the spring. A support arm having a hole therethrough extends perpendicularly from the writing instrument or a cap for the writing instrument near its top end. The threaded end of the clip arm is inserted through the hole from the bottom side so that the upper end of the spring rests against the bottom surface of the support arm. The fastener is secured to the upper end of the clip arm and holds the clip arm in the hold. The bottom edge of the fastener rests against the upper surface of the support arm. The spring is compressed slightly between the bottom surface of the support arm and the flange, so that in combination with the orientation of the support arm, the clip arm is biased toward the side of the writing instrument.
The clip can be connected to the cap or the body of a writing instrument. The clip can be used with pens, pencils, markers and non-marking stylii, among other types of writing instrument. The clip has a solid connection to the writing instrument with a separate, durable, flexible bias mechanism for holding the clip toward the writing instrument body. Although the bias spring is constricted partly by the support arm, they are separate components, so that using the bias mechanism does not require the support arm to flex or move.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.